Display screen or portion thereof with a graphical user interface



The file of this patent contains at least one drawing executed in color. Copies of this patent with color drawings will be provided by the United States Patent and Trademark Office upon request and payment of the necessary fee.

The single FIGURE is a front view of a display screen or portion thereof with a graphical user interface showing the new design.

The broken line showing a display screen or portion thereof, monitor and stand form no part of the claimed design. 

CLAIM The ornamental design for a display screen or portion thereof with a graphical user interface, substantially as shown and described. 